TORONTO - A man on trial for killing a Toronto police officer was psychotic at the time he rammed into the sergeant with a stolen snow plow and may be schizophrenic, court heard Thursday.

Richard Kachkar, 44, appears to have been suffering for several years from a “low-grade” mental illness with periodic spikes, such as in 2006 when he woke up in the middle of the night screaming that he was possessed by the devil and slapped his wife, a psychiatrist testified.

There was also a “very serious” exacerbation in the months before Kachkar killed Sgt. Ryan Russell in January 2011, forensic psychiatrist Dr. Philip Klassen testified.

“I formed the opinion that from a purely psychiatric perspective I felt that on the balance of probabilities he was not able to appreciate the nature and quality of his actions or their rightness or wrongness,” Klassen said.

Kachkar’s symptoms do not fit neatly into any one category, Klassen said, noting if he had to offer a diagnosis it would be either an unspecified psychotic disorder or possibly schizophrenia. Klassen added that he thought Kachkar was exaggerating his reported amnesia surrounding the death of Russell.

Kachkar has pleaded not guilty to first-degree murder and his lawyers are urging the jury to find him not criminally responsible — a finding that means he had a mental disorder and couldn’t appreciate what he was doing.

The judge has told the jury that there is “no doubt” Kachkar was driving the stolen plow on Jan. 12, 2011, when it hit and killed the 35-year-old officer, but what is at issue is Kachkar’s mental state.

Friends have said that in the days before Russell’s death Kachkar was behaving strangely, sleeping with his arms crossed like a mummy and talking about “white Jesus” and cameras being everywhere.

As he drove the stolen snow plow wildly around the streets of Toronto that morning for two hours he was yelling about the Taliban, Chinese technology, “Russian Facebook” and paramedics putting microchips in his body, his trial has heard.

Russell was killed after he got out of his cruiser to try to stop the snow plow, which was driving into oncoming traffic and crashing into other vehicles.

Klassen spent more than 10 hours interviewing Kachkar, spoke to his estranged wife and daughter and looked over voluminous other materials in preparing his report.

He described Kachkar as a man whose “grandiose” business schemes involved at various times the Kardashian sisters, a bakery for dogs and a Russian submarine. Among Kachkar’s possessions were pages of hand-written notes of plans for architecture, banking, commerce and information technology business ventures with the tabloid-fodder Kardashian family.

Klassen said when he asked Kachkar about the notes he “normalized” the plans, talking about their shared Armenian heritage.

“He stated that well, the Kardashian family is Armenian but they need help and he suggested that his talents could cover the various areas that you’ve seen and that he in turn could help them,” Klassen testified.

Based on his research, Klassen was also able to paint a picture of Kachkar’s early life — growing up in Edmonton with three sisters and hard-working immigrant parents — as unremarkable and middle-class. In his 20s Kachkar went to study architecture in Armenia, where he met his wife, though it seems their main reason for getting married was that she conceived, Klassen said.

They moved back to Canada, where he studied computerized design in British Columbia, then drifted around from job to job below his education level, Klassen said.

When his father died in 2004 Kachkar inherited $100,000 and tried to use the money flipping real estate in the United States, but he ultimately lost the properties to unpaid taxes after he didn’t get a work visa and couldn’t renovate them, Klassen said.

Kachkar took his son’s education money to buy a building in St. Catharines, Ont., where he was living until his arrest.

He was described by family as intrusive, controlling, argumentative and demanding, and police were called on a few occasions for incidents of pushing and shoving, Klassen said.

Kachkar and his wife separated around 2006, when she reported to social workers that she was worried about him because she thought he was mentally ill, Klassen said.